The application of geology to engineering ensures that the geological factors that affect the location, construction and maintenance of civil engineering works are perfectly recognised and applied in order to guarantee their safety. In this context, the aim of this work is to gather data on how geological studies are used in the municipality of Mossoro, Rio Grande do Norte state. The procedures adopted were bibliographical and documentary research and the collection of information in the field, carried out with companies that undertake civil engineering work. The results obtained indicate that there is constructive planning before, during and after the execution of the project, thus guaranteeing the structural stability, economy and technical viability of civil engineering works in the region. Finally, considerations are presented that illustrate the development of civil construction in the city, where housing and roadworks predominate.